If any western visitors wanted to visit Hagia Sophia prior to Fossati restoration, they needed a “firman”, a special permit from the sultan which was difficult to obtain. During the restoration, travelers had a chance to see the work. In 1934, the founder of Turkish Republic, Mustafa Kemal Ataturk, ordered the building to be transformed into a museum.

The uncovering of mosaics had already begun in 1931 by the leadership of Thomas Whittemore. This time the white plasters covering the mosaics were pulled out, carpets on the floor were removed and the original marble décor could be seen for the first time in centuries. Hagia Sophia Museum opened in 1 February 1935.